Washington State Ferries Saves Money using Underwater Drones

Cody Warner | September 19th, 2017

Washington State Ferries saves time and money by using a Deep Trekker Remotely Operated Vehicle, or underwater drone, for inspecting ship hulls.

Ferries are an essential part of transportation systems worldwide. In many countries waterway transportation for pedestrians is just as integral to a community as a car, bus or train. Puget Sound, located in Washington State, is a perfect example of a region reliant on ferry transportation.

An inlet of the Pacific Ocean, the area is home to a complex system of interconnected waterways including the Salish Sea, the Strait of Juan de Fuca and Deception Pass. With the second largest ferry system in the world (over 10.2 million vehicles carried per year ) Washington State has a staggering number of vessels to maintain. Every moment of downtime has a direct impact on the mobility of its passengers, the flow of traffic and the overall economy of the area. Ensuring regularly scheduled maintenance for the State ferries is paramount to detecting problems early and preemptively scheduling repairs to minimize the impacts.

Traditional Hull Inspections

The hardest area of the vessel to inspect is the hull of the ship since it is submerged and difficult to reach. Traditionally, Washington State Ferries would hire divers to inspect these hulls. This is costly and time-consuming (it takes a minimum of 30 minutes for divers to set up and get into the water). Not every defect, crack, corroded area or pit in a hull requires immediate action or repair either; sometimes it is important to see how these adjust over time, and having to pay for divers each and every time you'd like to have a look at a particular feature of the hull is unreasonable. That is where Cotty Fay, Chief Naval Architect for Washington State Ferries searched for an answer. What he found was a Remotely Operated Vehicle (ROV) otherwise known as an Underwater Drone, that is now referred to as "Nemo."

Washington State Ferries Inspecting Hulls with Underwater Drone

Washington State Ferries uses their DTX2 ROV to inspect the hull's seams, the propeller, the rudder and more. "The ROV gives us the sense right away if there's a problem or not," says Fay. "It's really important that we maintain and keep a good eye on everything we own and keep that equipment in good running order." Having their own ROV allows them to perform the regular inspections that they would have otherwise paid up to $5,000 a dive for divers to perform. They also now can perform inspections more regularly, they can call on their own equipment without having to get approvals or arrange for divers.

"If we lose a boat for half a day waiting for divers to show up, it can cost the public and economy a lot more than that. Yeah, it definitely paid for itself already, and we've only had it operating for about five months," Fay said.